Morphological and cytochemical studies of pathogenetic mechanisms in sclerotic vascular disease will be coordinated with biochemical analyses of subcellular fractions, secretions and whole tissues. Cellular mechanisms for the uptake, transport, digestion, secretion and storage of lipids, proteins, carbohydrates and metals will be studied, utilizing cytochemical procedures for demonstrating tracer compounds in the light and electron microscope. Enzymatic staining procedures for demonstrating the endoplasmic reticulum, mitochondria, Golgi apparatus, lysosomes and peroxisomes will be employed in arterial smooth muscle cells, alveolar epithelium, neurons, hepatocytes, reticuloendothelial cells, endocrine and other cell types from invertebrate and plant tissues in the investigation of structural-functional relationships of subcellular organelles.